JPH07223158A - Floating device - Google Patents

Abstract

PURPOSE:To easily adjust a resetting force by providing a ring type piston in a housing in such state as enclosing the external surface of a motor and having a forward end resiliently energized forward with fluid pressure for coming in contact with the rear end of an inner ring. CONSTITUTION:The flange section 41 of an inner ring 4 is formed to have spherical external surface and, therefore, the ring 4 turns in an counterclockwise direction about a contact point P1 with the ring type stopper 31 of a ring type cover body 3 as a support point. Furthermore, the inner ring 4 is inclined and comes in contact with the projection 24 of a piston 2 at a point P2, thereby pushing down the piston 2. When a burr on the lower side of a workpiece 14 is removed, the direction of an external force F changes. Only the positions of the points Pi and P2 change and the resetting force of the inner ring 4 becomes a constant force determined with the air pressure acting on the piston 2. When the external force F is reduced, the piston 2 pushes down the inner ring 4 due to the air pressure, and the ring 4 is thereby made to come in contact with the stopper 31. The radial direction of the ring 4 is restricted, while the spherical external surface of the flange section 41 thereof being guided with a guide bush 73. According to this construction, a tool can be properly positioned.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floating device, and more particularly to a tool holder for supporting a deburring tool such as a cutter or a grindstone, which can flexibly follow the tool with respect to a workpiece and exert a constant pressing force. The tool is centered while being generated.

[0002]

2. Description of the Related Art Conventionally, when deburring a work such as a mold using an industrial robot, a floating device has been provided to flexibly support a tool device having a tool attached to a drive source such as an air motor. Are

2 and 3 show examples of conventional floating devices. Deburring tool such as a cutter or grindstone at the tip 1
A tool housing 51 to which an air motor 1 that rotatably supports 2 is attached is supported in a floating state on a base housing 52 by springs 54 and absorbers 56 arranged in the circumferential direction of the end surface. In the base housing 52, as shown in FIG. 3, several holes (12 in FIG. 3) for springs 5 are evenly arranged in the circumferential direction.
9 and absorber holes 60 are alternately formed, and the absorber 56 or rod 5 is provided in each hole.
3 and a set of springs 54 are stored. A rod spring 53 whose tip is screwed into a hole on the end face of the corresponding tool housing 51 and a coil spring 54 are loosely fitted to the outer periphery of the spring hole 59, and the end of the spring hole 59 has a spherical inner surface. Seat 5 formed on
5 is fitted and fitted with the enlarged spherical surface formed at the end of the rod.

On the other hand, an absorber 56, which is threaded on the outer periphery, is screwed into the absorber hole 60, and the end of the piston rod 57 of the absorber protruding at the tip of the absorber 56 is screwed to the end of the tool housing to form a stopper 58. Is abutted against. The absorber 56 has a piston slidably fitted in a cylinder, a piston provided with a throttle valve, and a piston rod 57 protrudingly provided on one side.
A spring is inserted into the other end so that the piston rod is projected outward.

The base housing 52 is gripped by the wrist of an industrial robot, and while the tool 12 is not in contact with the workpiece, the springs in all directions extend in the elastic direction to center the tool 12 on the base housing 52. Floating supported. When the tool 12 is pressed against the workpiece, the resistance causes the tool housing 51 to tilt and the tilted spring to be compressed. At that time, the absorber 56 operates to absorb and attenuate banding and vibration.

However, in these conventional examples, since many parts such as spring rods and receiving seats at six positions in the circumferential direction are used for centering, it is difficult to obtain centering accuracy, and at the same time, six springs are used. Since the restoring force is applied, the restoring force varies depending on the directionality of the spring, and if you want to change the restoring force, you have to replace the spring and it is difficult to adjust the restoring force. It was

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is easy to adjust the restoring force, the restoring force is the same in any direction, the centering accuracy is high, and the total length is short. It is an object of the present invention to provide a floating device having a compact structure.

[0008]

In order to solve the above-mentioned problems, in a floating device of the present invention, a motor having a tool shaft at its tip is supported by an inner ring, and the inner ring is tiltably supported with respect to a casing. The rear end of the inner ring is in contact with the front end of a ring-shaped piston provided in the housing on the outer periphery of the rear part of the motor, and the compressed fluid of a constant pressure is supplied to the rear end of the ring-shaped piston to move the inner ring. It is configured to be pressed forward by a uniform constant pressure, and the tip of the flange portion of the inner ring abuts a stopper provided on the housing to center the tool shaft.
Further, the outer periphery of the flange portion provided at the rear end portion of the inner ring is formed in a spherical shape, and is guided outside by a guide ring made of a bearing metal provided in the housing. When an external force is generated on the tool shaft, the inner ring tilts and pushes the ring-shaped piston against the fluid pressure at one location on the inner ring end surface.

[0009]

With the above configuration, in a normal state, when compressed fluid is supplied to the rear portion of the ring-shaped piston, the front end of the ring-shaped piston presses the rear end portion of the flange portion of the inner ring,
The inner ring is guided by a guide ring formed of a bearing metal that contacts the outer periphery of the flange portion to move forward, and its front end abuts on a ring-shaped stopper projecting on the housing to perform accurate centering. When an external force is applied to the tool shaft during machining of a workpiece with a tool, the inner ring contacts the stopper at one point on the front surface of the flange and tilts with that point as the fulcrum, pushing the ring-shaped piston back and making it ring-shaped. The piston is held at a position balanced with the pressure of the fluid loaded on the rear end of the piston. When the external force disappears, the ring-shaped piston advances again, the front surface of the flange portion of the inner ring contacts the stopper, and accurate centering is performed. When changing the pressing force of the tool on the workpiece, change the set pressure of the fluid. Can be done easily.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIG.

FIG. 1 is a sectional view showing the entire floating device of the present invention. Reference numeral 9 is a wrist of an industrial robot, which is rotatable and movable, and has a tip for deburring work of the present invention. The tool unit supported by the floating device is fixedly supported. 7 is the wrist part 9 of the robot
The housing of the floating device of the present invention is fixed to the inner sleeve 8 at the rear end and the lid 3 at the front end. A guide bush 72 formed of a bearing metal for guiding the ring-shaped piston 2 is fitted on the inner circumference of the housing 7, and a front large-diameter recess 71 of the housing 7 is fitted with a flange guide of an inner ring, which will be described later. A bearing metal guide bush 73 for the vehicle is similarly fitted.

Reference numeral 2 is a ring-shaped piston slidably fitted in a ring-shaped cylinder formed between the housing 7 and the inner sleeve 8, and an air source is provided at an air port 23 at the rear end of the cylinder. Compressed air supplied from 21 through the relief pressure reducing valve 22 is elastically pushed and pressed forward. The relief pressure reducing valve 22 is provided with a lever (not shown) that changes the pressure of the spring 22a. The operator operates the lever to change the pressure of the spring 22a, and the air supplied to the rear end of the cylinder is changed. The pressure can be changed. The tip portion 24 of the ring-shaped piston 2 is formed with a taper-shaped ring-shaped projection so as to reduce the diameter, and the tip thereof is configured to abut the rear end surface of the inner ring 4. On the outer peripheral surface of the ring-shaped piston 2, an O-ring 74 fitted in a recess formed in the inner peripheral portion of the housing is provided so as to come into contact with the recess. A flange portion 41 of the inner ring 4 supporting the tool-equipped air-motor 1 is loosely fitted in the large-diameter portion 71 of the housing 7, and is held by the ring-shaped lid 3 so as not to come off from the tip.

The front portion of the inner ring 4 penetrates through the ring-shaped lid body 3 and projects to the front portion, and a flange portion 41 is formed on the rear portion, and the front end of the flange portion 41 projects to the rear surface of the ring-shaped lid body 3. It is configured to abut the ring-shaped stopper 31. The outer periphery 42 of the flange portion 41 of the inner ring 4 is formed in a spherical shape, and the spherical shape allows the guide bush 73 to be formed.
It is configured to be slidable and tiltable inside.

Further, a radial groove 43 is provided on the rear end surface of the flange portion 41 and engages with a detent pin 6 projecting inside the housing 7 to provide a rotational reaction force of the air-motor. Has been stopped. Reference numeral 32 denotes a seal member that is interposed between the ring-shaped lid 3 and the inner ring 4 to prevent dust and the like from entering the inside of the hound, and is made of sponge or the like. The air-motor 1 is fixed to the inner ring 4, a deburring tool 12 such as a cutter or a grindstone is fixed to the tip of the rotary spindle 11, and the pipe 1 at the rear end is fixed.
It is driven to rotate by the compressed air supplied from No. 3. 1
Reference numeral 4 denotes a workpiece to be deburred, and 14a denotes burrs of the workpiece.

The floating device of the embodiment of the present invention is constructed as described above, and its operation is as follows. First, in a state where the robot is fixed to the wrist portion 9 and is suspended, air is supplied via the air source 21 and the relief pressure reducing valve 22.
The ring-shaped piston 2 advances due to the air pressure supplied from the port 23, and pushes the inner ring 4 by the ring protrusion 24 at the tip thereof. The outer periphery of the flange portion 41 of the inner ring 4 is guided by the guide bush 73 to move forward, and the front surface of the flange portion 41 comes into contact with the ring-shaped stopper 31 provided on the inner surface of the ring-shaped lid body 3 of the housing 7 to stop. That is, the radial position of the inner ring 4 is regulated by the guide bush 73 and the longitudinal position thereof is regulated by the ring-shaped stopper 31, and the pressing force thereof is determined by the air pressure in the cylinder, so that the tool 12 is accurately centered.

Next, the robot is moved to press the tool 12 against the burr 14a of the workpiece 14 from above, and the robot is moved to move the tool 12 following the upper surface of the workpiece 14. During machining, when the tool 12 receives an upward external pressure F corresponding to the size of the burr 14a, the inner ring 4 fixedly integrated with the tool 12 integrally rises to the right as shown by the chain double-dashed line in FIG. Becomes When the tool 12 is repeatedly moved along the upper surface of the workpiece 14, the burr 14a is finally removed and the tool 12 is pushed by the piston 2 to be in the state shown by the solid line. Since the outer periphery of the flange portion 41 of the inner ring 4 is formed into a spherical shape, it rotates counterclockwise about a contact point P1 (lower part in the figure) of the ring-shaped lid 3 with the ring-shaped stopper 31 as a fulcrum. The inner ring 4 inclines and contacts the protrusion 24 of the piston 2 at the point P2 to push down the piston 2. When the burr on the lower part or the side part of the work piece 14 is removed, the direction of the external force F is changed and only the positions of the points P1 and P2 are changed, and the restoring force is determined by the air pressure acting on the ring-shaped piston 2. It becomes constant power. When the external force F decreases, the inner ring 4 is pushed by the ring-shaped piston 2 by the air pressure,
31 and the guide bush 73 radially restricts the outer peripheral spherical surface of the flange of the inner ring,
Centering can be performed at accurate positions in the radial direction and the front-back direction, and the tool can be positioned accurately.

At this time, the ring-shaped piston 2 moves left and right, but the O-ring 74 is in contact with the outer peripheral surface of the ring-shaped piston 2 and acts as an absorber by its frictional resistance to absorb the tilting vibration of the air motor 1. To be done.

The air motor 1 according to the above-described embodiment is used.
Although the example using is described, any motor may be used as long as it rotates the tool 12, for example, an electric motor may be used. Further, in the above-described embodiment, the example in which the air is supplied to the port 23 has been described, but any fluid that operates the piston 2 may be used, for example, oil may be used. Air is the best in terms of keeping the work environment clean even if it leaks from the housing 7.

[0019]

With the above-described structure, in the floating device of the present invention, the restoring force is determined only by the fluid pressure applied to the ring-shaped piston 2, so that the same restoring force acts regardless of the direction in which the inner ring 4 is tilted. However, there is an effect that the restoring force can be changed only by changing the setting of the fluid pressure.

The tool is positioned by the stopper 3
Since it can be performed with only four parts including the inner ring 4, the inner ring 4, the guide bush 73, and the piston 2, the positioning accuracy is significantly improved.

Further, in the present invention, since the elastic means is a ring-shaped piston and is arranged on the outer periphery of the motor, the total length of the floating device can be shortened and the whole structure can be made compact. Is played.

[Brief description of drawings]

FIG. 1 is a sectional view showing an entire floating device according to an embodiment of the present invention.

FIG. 2 is an overall sectional view showing an example of a conventional floating device.

FIG. 3 is a component diagram of the conventional housing shown in FIG.

[Explanation of symbols]

 1 Air Motor 2 Ring Piston 4 Inner Ring 6 Non-rotating Pin 7 Housing 8 Inner Sleeve 12 Deburring Tool 31 Stopper 73 Guide Bush

Claims (1)

[Claims] 1. An inner ring for supporting a motor having a tool shaft,
A housing that tiltably supports the inner ring; a ring-shaped piston that is disposed in the rear part of the housing so as to surround the outer periphery of the motor and that is elastically bulged forward by fluid pressure so that the tip end contacts the rear end of the inner ring; A floating device comprising a ring-shaped stopper provided on the housing so that the tip of the inner ring contacts.